1. Field of the Invention
This invention relates to an improvement in a cylinder block of an automotive internal combustion engine, equipped with an engine knock sensor.
2. Description of the Prior Art
It is well known that knocking preventing devices have been already put into practical use, for example, in high compression ratio engines and engines equipped with a supercharger. Such knocking preventing devices are arranged to detect engine knock generation by sensing the vibration of a cylinder block, and suppress the engine knock, for example, by retarding spark timing in response to the detected engine knock generation. However, this engine knock sensor is usually located on a water jacket outer wall section defining thereinside a water jacket, and therefore engine knock generated in an engine cylinder is subjected to damping action by the water jacket, thus deteriorating the sensing accuracy of the engine knock sensor.